JPH0110832Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a three-action pressure switch installed in a refrigerant passage on the high pressure side of an automobile cooling system.

``Prior art'' A switch that opens an electrical contact to stop a compressor when the pressure on the high pressure side of a refrigerant passage in a refrigeration cycle drops or rises abnormally, and when the pressure on the high pressure side is in a normal state, For example, a pressure switch that has a switch that can arbitrarily determine the pressure switch for switching electrical contacts between open and close is
There is number 180344. However, as shown in FIG. 8, this type of switch has an electric switch 51 for high voltage and low voltage.
is assembled into the lower body 52, then the high voltage reversing disk 53 is installed, and the medium voltage electric switch 54 is further installed.
After the reversing disk 53 is installed, it is not possible to reselect the high-pressure reversing disk 53 which has a different reversing operation timing, and as a result, disassembling it again is extremely time-consuming and inefficient.

``Problems to be solved by the invention'' In conventional switches of this type, the stroke of the rod operates only downward, so the housing that accommodates the rod becomes large and requires a large amount of ammunition to lift the rod upward. The triggering means also uses a coil spring with a long stroke, but in this invention, at least one of the rods that operate the electric switch is operated in the opposite direction from the middle to shorten the movable stroke, making the switch more compact. The purpose is to make the

"Means for Solving the Problems" The configuration of the present invention is that a diaphragm is airtightly fixed between an upper body and a lower body having a pressure inlet to form a pressure receiving chamber in the upper body, and a pressure receiving chamber is formed in the lower body. In a pressure switch having first and second electric switches, the upper surface is equipped with a first reversing disc that is reversible downward, and the lower surface is equipped with a perforated second reversing disc that is reversible upward. A perforated piston is housed in a holder for vertical movement,
The holder is housed in a lower body so as to be movable up and down, and the holder has an actuating protrusion in the middle part thereof that inverts the second inversion disk upward, and a cylindrical second rod having a head in the center. A guide part that is mounted so as to be movable up and down is provided, and a disc spring having a hole through which the guide part is inserted is hooked to the lower body wall. A switch is installed,
The upper end of the elongated second rod penetrates the hole in the piston, the second reversing disk, the first rod, and the first electric switch, and its upper end is locked to the first reversing disk, and the lower end is connected to the second electric switch. The lower end of the first rod is brought into contact with the first electric switch.

``Function'' The present invention uses a perforated disc spring with its reversing direction reversed, and also changes the operating direction of the rod midway, thereby shortening the stroke and thereby improving the structure of the electric switch. I was able to simplify the switch and make it smaller.

"Embodiment" An embodiment of the present invention will be described based on the drawings. A lower body 4 is fitted below an upper body 2 having a pressure introduction port 1 at the upper part, and there is a flexible space between the two. The peripheral edge of the diaphragm 3 is clamped and fixed together with a seal packing 5, and a pressure receiving chamber 6 communicating with the pressure introduction port 1 is provided above the diaphragm 3. Lower body 4
A locking part 8 is provided at the lower part of the inner wall of the housing via a locking step part 7, and furthermore, a working chamber 9 with a slightly smaller diameter is formed below the lower body 4, and a slightly larger diameter working chamber 9 is formed above the lower body. There are 10 vacant rooms. Reference numeral 12 denotes a holder housed in the empty chamber 10 so as to be movable up and down, and a locking step 7 is provided below.
It descends until it stops at the peripheral edge of the rising wall 1.
3, and an actuating convex portion 14 is provided concentrically upwardly protruding in the middle portion, and a concave portion 15 formed in a slightly larger size is formed in a cylindrical shape with a slightly smaller diameter in a continuous manner below the center. A guide portion 16 is provided. Reference numeral 17 denotes a disc spring whose outer periphery is hooked to the hooking portion 8, whose center projects upward in a normal state, and which has a hole 18 in the center through which the guide portion 16 can be inserted. Reference numeral 20 designates a cylindrical first rod which has a large diameter head 19 that fits into the recess 15 of the holder and which is inserted into the guide portion 16 so as to be movable up and down. 22 is a second reversing disk for high pressure operation which has a hole 23 in the center and projects downward under normal conditions, and is placed concentrically on the upper surface of the holder, and further above this holder. A piston 25 is housed so as to be movable up and down, and has a hole 26 in the center thereof, and the above-mentioned housing part 27 is provided on the upper surface, and a first reversing disk that operates under medium pressure is provided in the upper housing part. 29 is housed in a normal state so as to protrude upward. Further, a lower accommodating portion 28 is also formed on the lower surface of the piston 25, and this lower accommodating portion 2
The second reversing disk 22 is accommodated within the second inverting disk 8 .
Two pairs of terminal plates 31 and 3 are provided on the lower surface of the lower body 4.
3, 38, and 40 are protruded, respectively. That is,
The first fixed contact 32 is attached to the upper end of one first terminal plate 31 located above, and the first fixed contact 32 is attached to the upper end of one first terminal plate 31 located above.
The root of a first leaf spring 34 is fixed to the upper end of the leaf spring 3, and a first electric switch 36 for low and high pressures is formed by a first movable contact 35 attached to the tip of the leaf spring and the fixed contact 32. It has been done. Note that a hole 37 is bored in the middle of the first leaf spring 34.

A second fixed contact 39 is fixed to the upper end of one second terminal plate 38 located below, and a root portion of a second leaf spring 41 is fixed to the upper end of the other second terminal plate 40, and the tip A second movable contact 42 that connects and separates from the second fixed contact is attached to the second fixed contact, and a second electric switch 43 for medium voltage is provided at both contacts. 45 is a hole 26 provided at the center of the piston and a second reversing disk 22
A long second rod 45 passes through the hole 23 provided at the center of the holder and the through hole 21 of the first rod 20 housed in the guide portion 16 of the holder, and the upper end of the second rod is connected to the first inversion circle. It is locked to the plate 29, and the lower end is in contact with the upper surface of the second leaf spring 41.
Note that the lower end of the first rod 20 is in contact with the upper surface of the first leaf spring 34.

Next, to explain the operation of this embodiment, when external pressure enters the pressure receiving chamber 6 from the pressure introduction port 1, the first reversing disk 29 in contact with the diaphragm 3
The depressing force of the piston is transmitted to the disc spring 17 via the second reversing disc 22 and the holder 12, and bends the disc spring 17 downward. Next, when the pressure inside the pressure receiving chamber 6 reaches _P1 , the piston 25 pushes down the holder 12 via the second reversing disk 22, and the disc spring 17 supporting the holder 12 from below moves as shown in FIG. As shown in the figure, the holder 12 bends further downward and descends until the lower surface of the holder 12 is locked with the locking stepped portion 7, and as a result, the first rod 21 attached to the guide portion 16 of the holder
is lowered to push down the first leaf spring 34, connect the first movable contact 35 to the first fixed contact 32, and close the first electric switch 36. In this case, the first and second reversing discs 29 and 22 do not yet perform the reversing operation.

Next, when the pressure inside the pressure receiving chamber 6 reaches P ₂ ,
As shown in FIG. 3, the first reversing disk 29 reverses downward and momentarily pushes down the second rod 45, and the lower end of the second rod 45 pushes down the second leaf spring 41. Second electric switch 4
Close 3. In this case, the first electrical switch 36 remains closed.

The outer peripheral edge 22a of the second reversing disk 22 is locked to the lower storage chamber 28, and the sloped portion 22b is pressed upward by the operating convex portion 14 of the holder 12 and is held in a sandwich-like manner. Therefore, when the pressure inside the pressure receiving chamber 6 further increases and reaches P ₄ , the second inversion disk 22 momentarily turns upward as shown in FIG. 4, and as a result, the second inversion disk 22 1st
The first leaf spring 34, which has been pushed down via the rod 20, is lifted upward by its elastic force and opens the first electric switch 36. In this case, since the first inversion disk 29 remains inverted downward, the second rod 45 remains pressed down, and therefore the second electric switch 43 remains closed. In this way, pressure control is performed by combining two reversing discs that operate in different reversing directions in response to pressure changes and a disc spring.

"Effects of the invention" The invention as described above has the following effects.

The movement of the first rod that opens and closes the second electric switch is not simply downward as in the conventional case.
Since the rod can move upward from the middle, the movable range of the rod can be shortened, and as a result, the stroke of the spring supporting the rod can be reduced, and the electric switch can be downsized and the structure can be simplified.

By providing holes in the centers of the piston, holder, disc spring, and reversing disk, the first and second electric switches are installed in the lower body.
Since two reversing disks can be incorporated, the operating pressure can be easily adjusted by reselecting the reversing disks.

By providing each electric switch with a hysteresis, it is possible to prevent chattering and wear of the contacts, thereby increasing durability.

The parts are easy to assemble, the electric switch is small and simple, and the switch assembly work efficiency is further improved, making it suitable for mass production.

The second and fourth set pressures on the high pressure side each utilize the reversing operation of the reversing disc, so that switching can be performed instantaneously.

Since this device can function as three pressure switches, it can be made smaller and lighter, and is convenient to handle, making it suitable for in-vehicle use.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; Fig. 1 is a longitudinal sectional view of the whole, Figs. 2, 3, and 4 are sectional views showing the operating states, and Fig. 5 shows the pressure of the disc spring on the low pressure side. 6 is an explanatory diagram showing the displacement of the inversion disk on the medium pressure side with respect to pressure. FIG. 7 is an explanatory diagram showing the displacement of the inversion disk on the high pressure side with respect to pressure. FIG. 3 is a sectional view of the switch. 12... Holder, 14... Operating convex portion, 16...
... Guide part, 17 ... Disc spring, 20 ... First rod, 22 ... Second reversing disk, 25 ... Piston,
29...First reversing disk, 36...First electric switch, 43...Second electric switch, 45...Second rod.

Claims (1)

[Scope of utility model registration request] In a pressure switch, a diaphragm is airtightly fixed between an upper body and a lower body having a pressure introduction port to form a pressure receiving chamber in the upper body, and first and second electric switches are provided in the lower body, A perforated piston having a first inverting disk that inverts downwardly mounted on the upper surface and a second perforated inverting disk that inverts upwardly mounted on the lower surface is housed in a holder so as to be movable up and down, and the holder is accommodated in the lower body so as to be movable up and down, and the middle part of this holder has an actuating protrusion that inverts the second inversion disk upward, and a cylindrical first rod with a head in the center that can be moved up and down. A movably mounted guide part is provided, and a disc spring having a hole through which the guide part is inserted is hung on the lower body wall, and below the disc spring, the first and second electric switches are arranged at different heights. The upper end of the elongated second rod passes through the hole in the piston, the second reversing disk, the first rod, and the first electric switch, and the upper end of the second rod is fixed to the first reversing disk, and the lower end is fixed to the first reversing disk. A three-action pressure switch comprising a second electric switch and a lower end of the first rod in contact with the first electric switch.